GUI: Overhaul the file renamer configuration dialog based on a design of...

GUI: Overhaul the file renamer configuration dialog based on a design of Scott's. This involved a lot more code than I thought at first, but it should be pretty neat.
This also should fix wish 64849 (Add genre to file renamer) and wish 63912.
In essence this creates a dialog that has a row with each possible category, and arrows allowing you to move that category up and down.
* In the options for the category, you can control leading and trailing text, and what happens if the tag is empty.
* You can set a minimum width for the track (bug 63912).
* The dialog includes a sample result, and you can either edit the sample tag values manually, or load tags from a file to see what it would look like.
* Right now the file renamer code automatically suppresses separators between tag values that use bracketing characters, since I feel that stuff like Artist - Title - [Track] looks dumb, but that may be changed/removed later.
Suggestions are accepted: michael (dot) pyne (at) kdemail (dot) net.
BUG:63912
BUG:64849
svn path=/trunk/kdemultimedia/juk/; revision=359516